Improvement in gates for swinging bridges



@jaar arpa;

LAURIT'Z'ANDERSON, or onload-o, ILLrNois.

` y Lam Partnr No. 97,855, dated December 14,1869,

IMPROVEMET IN GATES FOR `SilVING'rING BRIDGES.

' The Sohedulejrcl'erred to' in these Letters Patent and maling part of the sameA i To all whom fit may concern V Beit known that I, LAURITZ ANDERSON, of Olii cago, in the county of Cook, and State oi Illinois, have invented anew and valuable Improvement in Gates for Swinging Bridges; land I do hereby declare that the following is a full, clear, and exact description of the construction and operation of the same, reference being had tothe annexed drawings, making a part of this specification, and to the letters andfiguresof `reference marked thereon. Figure 1, of the drawings, is arepresentation of my invention, in perspective, as the draw is moving from the `bridge-head. i

Figure 2 is a representation of the gate attached to bridge-head, as it appearswhen the draw is closed and gate down.

Figure 3 isa sectional view. My invention relates to draw bridges,"and consists, mainly, in the construction and novel arrangement of deviceswhereby the sheerlendsof the bridge-heads are automatically closed by gates,f\vl1icl`1 rise in place as `the, draw moves away.

lhe letter A, of the drawings, designates the draw,

-only one end of which is shown, as the gate at the l.other end 1s constructed and operated in like manner.

.the end ofthe draw, and lined with suitable metal.

The bridge-head By is provided with a crossbeam,

`O, to theupper surface owln'ch are securedrthree `plates of inet-al, through which pass the three perpendicular guide-rods of the gate.

l-he gate D consists of three perpendicular rods,` al,

il', and df, to the upper ends of, which is secured ythe horizontal bar l1.

Between the rods are fastened thebraces k, and

' just above the point at which these braces abut against `the central rod h, a pin, n, isfinmed, aboutwhich rotates an anti-friction roller, which plays in the slot a Y in the'end or' the draw.-

To the lower end of the centrall guide-rod d is attache-d one end of a chain, which, passing over the pulleyp, is attached by the other end to aweigbt, I,

` which counterbalauces the weight ofthe gate.

rod d, when the draw, moving away, leaves the upper arm of the lever free.

This upper arm -is an elbow projected above the surface ofthe cross-beam C, so that the draw-frame, inv passing over it, will press itdown, and thereby move the ledge from under the rod d, allowing the gate to descend.

AThe operation ofthe gat-e is as follows: l

The draw 4being closed, the gate is down, and its anti-friction roller 'u is in the iowermost part ot' the slot oi' the draw. lever S is depressed, and the ledge at the end of its lower arm is away from the rod d. ,N ow, as the draw moves away in swingingupon its pivot, theslot a' in itsend gradually carries up the roller v'1n/and -with it the gate I).

balance-weight I, and by the lodge on the lower end ot' the lever S, which, as soon as the end of the draw is removed, is drawn, by the action oi' the spring c `under the lower end of' the rod d.

In closing the draw, the open endiof the slot a' catches the roller u, and as the frame of thel draw, at the same time, by pressing on fthe elbow-armof the lever S, frees the lower end of the rod d, the gate is pulled gradually down, between the bridge-head and end of the draw, until the horizont-al bar lt is below the pianking.

The weight I being just sutiicient to counterbaiance the weight of the gate D,oti'ers little or no resistance to the movement of the draw, therefore requiring `for its operation the expenditure ot' no more power than `is at present necessary.

What I claim as my invention, and desire to secure by Letters Patent, is-

The gate B, counterpoised bya weight, and provided with a projecting pin or stud, a, in combination with the groove a in the end of the turning bridge, andthe locking-lever S, all constructed and arranged to operate substantially as described.

. In testimony that I claim the above,1h ave here `unto subscribed my name, in the presence of two wit- IIGSSBS. Y

Witnesses: LAURITZ ANDERSON.

D. HARRY HAMMER, R. B. Fownnn.-

At the same time, the elbow of the At last the. slot a? leaves the' roller alto- 4 getlier, but the gate is` prei-'exited from falling by the 

